(CNN) -- The military psychiatrist accused of killing 13 people in a Fort Hood shooting spree has been admitted to an Army hospital in Texas for treatment of an undisclosed condition, according to a statement from the military on Monday.
Maj. Nidal Hasan was admitted Saturday to Carl Darnal Medical Center and is expected to be released within 48 hours, Fort Hood's public affairs office said around noon.
The military did not disclose why Hasan was in the hospital, citing federal government regulations against conveying patients' medical information. He was in "good condition" Monday, according to Fort Hood.
His lead military attorney, Lt. Col. Chris Poppe, said only that his client wasn't suffering from a self-inflicted wound.
Hasan's court-martial tied to the 2009 mass shooting had been scheduled to start last month at Fort Hood, Texas. But the Army Court of Criminal Appeals this month delayed its start indefinitely to determine whether his beard can be forcibly shaved during trial.
CNN's Larry Shaughnessy contributed to this report.